[ForHackernews]

You can read up on gene drive, but the short version is that it's a devious genetic-engineering trick so that if even one copy of the allele is present, all offspring will get it: https://en.wikipedia.org/wiki/Gene_drive#/media/File:Gene_Dr...

The allele will replicate itself onto the homologous chromosome. Another way to think of it is that an allele from a gene-drive parent will wipe out and copy itself over the allele from the other parent.

It'd be like if instead of the only the phenotypic expression of brown eyes being dominant over blue eyes, rather the brown gene actually wiped out the blue gene so no blue-eyed children could be born from a pairing of one brown-eyed and one blue-eyed parent.